1261386000 has 640 divisors, whose sum is σ = 5348229120. Its totient is φ = 278208000.

The previous prime is 1261385959. The next prime is 1261386011. The reversal of 1261386000 is 6831621.

1261386000 is a `hidden beast` number, since 1 + 26 + 1 + 38 + 600 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 17765965 + ... + 17766035.

It is an arithmetic number, because the mean of its divisors is an integer number (8356608).

Almost surely, 2^1261386000 is an apocalyptic number.

1261386000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1261386000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2674114560).

1261386000 is an abundant number, since it is smaller than the sum of its proper divisors (4086843120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261386000 is a wasteful number, since it uses less digits than its factorization.

1261386000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157 (or 135 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 1261386000 is about 35515.9963959904. The cubic root of 1261386000 is about 1080.4781833089.

The spelling of 1261386000 in words is "one billion, two hundred sixty-one million, three hundred eighty-six thousand".